Behavior of Reinforced Concrete Beams Strengthened in Shear Using L-Shaped CFRP Plates: Experimental Investigation
Behavior of Reinforced Concrete Beams Strengthened in Shear Using L-Shaped CFRP Plates: Experimental Investigation
复制标题
DOI：
10.1061/(asce)cc.1943-5614.0000398
复制
发表时间：
2014-04-01
影响因子：
4.6
通讯作者：
Shao, Yixin
中科院分区：
文献类型：
--
作者：
Mofidi, Amir;Thivierge, Sebastien;Shao, Yixin
本文介绍了用预制 L 形碳纤维增强聚合物 (CFRP) 板进行剪力改造的钢筋混凝土 (RC) T 梁的实验研究结果。 L 形纤维增强聚合物 (FRP) 板对 RC 梁的抗剪加固已被证明是有效的。在该方法中，在整个梁翼缘上开槽，以将垂直于 RC 梁纵轴的 L 形 CFRP 板的垂直腿完全嵌入 RC 梁腹板表面中。然而，在某些情况下，由于 RC 梁翼缘中存在诸如纵向钢等障碍物，在混凝土翼缘上钻孔可能不可行。因此，本次研究的主要目的是评估外部粘结（EB）L 形板抗剪加固的 RC 梁的性能受 L 形 FRP 板嵌入长度的影响。总共对 2,500 毫米长的 T 梁进行了六次测试。使用 RC 梁翼缘中具有不同嵌入长度的环氧树脂粘合 L 形 CFRP 板对三个试件进行抗剪加固。一个样本通过在混凝土梁翼缘中完全嵌入 CFRP 板进行抗剪强化。第二个样本通过部分嵌入 L 形 CFRP 板进行加固。该样本代表了由于障碍物而无法完全穿透 CFRP 板的情况。在此样本中，埋置长度设置为 25mm，以模拟 RC 梁中的最小混凝土保护层厚度。第三个试件采用 L 形 CFRP 板进行剪切强化，未嵌入混凝土梁翼缘。此外，还对采用 L 形 CFRP 板加固的梁的性能与未预埋 EB FRP 板加固的类似试件的性能进行了比较。结果表明，梁翼缘部分和全埋L型CFRP板加固试件的性能优于EB FRP板和未预埋L型CFRP板加固梁。
This paper presents the results of an experimental investigation on reinforced concrete (RC) T-beams retrofitted in shear with prefabricated L-shaped carbon fiber-reinforced polymer (CFRP) plates. Shear strengthening of RC beams with L-shaped fiber-reinforced polymer (FRP) plates has proved effective. In this method, grooves are made throughout the beam flange to fully embed the vertical leg of the L-shaped CFRP plate perpendicular to the longitudinal axis of the RC beam and in the RC beam web surface. However, in some cases, drilling grooves in the concrete flange might not be feasible because of the presence of obstacles such as longitudinal steel in the flange of the RC beams. Therefore, the main objective of this investigation was to evaluate the performance of the RC beams strengthened in shear with externally bonded (EB) L-shaped plates as affected by the embedment length of the L-shaped FRP plates. In total, six tests were performed on 2,500-mm long T-beams. Three specimens were strengthened in shear using epoxy-bonded L-shaped CFRP plates with different embedment lengths in the RC beam flange. One specimen was shear-strengthened with fully embedded CFRP plates in the concrete beam flange. The second specimen was strengthened with partial embedment of the L-shaped CFRP plate. This specimen is representative of the case where full penetration of the CFRP plate is not feasible because of an obstacle. In this specimen, the embedment length was set to 25mm to simulate the minimum concrete cover thickness in RC beams. The third specimen was shear-strengthened with L-shaped CFRP plates with no embedment in the concrete beam flange. In addition, the performance of the beams strengthened with L-shaped CFRP plates was compared with that of a similar specimen strengthened with EB FRP sheets without embedment. Results show that the performance of the specimens strengthened with partially and fully embedded L-shaped CFRP plates in the beam flange was superior to that of the beams strengthened with EB FRP sheets and L-shaped CFRP plates with no embedment.